American Journal of Botany最新文献_第9页

High-elevation endemic plants predicted to lose habitat from changing climate in Washington State. 高海拔地区特有植物预计将因华盛顿州气候变化而失去栖息地。

IF 2.7 2区生物学

American Journal of Botany Pub Date : 2026-05-02 DOI: 10.1002/ajb2.70195

Nicholas L Gjording, Erik W Ertsgaard, David E Giblin, Iris H Dimpsey, Owen B Bard

{"title":"High-elevation endemic plants predicted to lose habitat from changing climate in Washington State.","authors":"Nicholas L Gjording, Erik W Ertsgaard, David E Giblin, Iris H Dimpsey, Owen B Bard","doi":"10.1002/ajb2.70195","DOIUrl":"https://doi.org/10.1002/ajb2.70195","url":null,"abstract":"Premise: High-elevation plants face unique challenges from potential climate change impacts that will likely require upslope migration into increasingly smaller suitable habitat. This situation is particularly acute for endemic species that by definition occupy small geographic ranges. Here we assessed climate risk for eight endemic species occurring in the Cascade Range of Washington State and modeled their ability to persist through the end of the century.Methods: For current species distributions, we utilized online georeferenced herbarium specimen and observation data from Pacific Northwest herbaria and iNaturalist. We visualized future climate impacts on current habitat space for each species using principal component analysis under two future CO2 emission levels: SSP245 and SSP585. We then applied an ensemble modeling approach using spatial data for climate, canopy cover, topography, and geology to predict future suitable habitat for each species.Results: Our models predicted substantial habitat area losses for seven of eight species examined, with four expected to lose 99-100% of suitable habitat if CO2 emissions continue at current levels (SSP585). Under reduced CO2 emissions levels (SSP245), an average of 26.8% of the habitat area loss for each species can be abated.Conclusions: While our models show habitat range shifts for these species, it remains uncertain whether any species will successfully migrate into future potential suitable habitat. Habitat loss predicted in this study informs potential conservation needs. We present a repeatable modeling framework for studying climate change impacts on habitat for targeted species using publicly available distribution and environmental data.","PeriodicalId":7691,"journal":{"name":"American Journal of Botany","volume":" ","pages":"e70195"},"PeriodicalIF":2.7,"publicationDate":"2026-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147809622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

IF 2.7 2区生物学

American Journal of Botany Pub Date : 2026-05-02

引用次数: 0

IF 2.7 2区生物学

American Journal of Botany Pub Date : 2026-05-02

引用次数: 0

One-step, two-step: Whole-genome-duplication pathways in Artemisia tridentata and potential consequences for genome evolution. 一步，两步：三叉戟蒿的全基因组复制途径及其对基因组进化的潜在影响。

IF 2.8 2区生物学

American Journal of Botany Pub Date : 2026-05-01 DOI: 10.1002/ajb2.70206

Lukas P Grossfurthner, Nurul Islam-Faridi, Paul A Hohenlohe, Lisette P Waits, Bryce A Richardson

{"title":"One-step, two-step: Whole-genome-duplication pathways in Artemisia tridentata and potential consequences for genome evolution.","authors":"Lukas P Grossfurthner, Nurul Islam-Faridi, Paul A Hohenlohe, Lisette P Waits, Bryce A Richardson","doi":"10.1002/ajb2.70206","DOIUrl":"10.1002/ajb2.70206","url":null,"abstract":"Premise: The presence of more than two full chromosome sets, polyploidy, is an important component in plant evolution. However, knowledge of the frequency of polyploidization and which pathways contribute to polyploid formation and gene flow among cytotypes remains limited.Methods: Flow cytometry and chromosome counts were used to determine genome size of Artemisia tridentata parents and offspring. Reduced-representation sequencing was used on the parents, offspring, and conspecific taxa to confirm genetic relationships among parents and offspring.Results: A polyploidization rate of 0.22% was determined from seedlings of diploid parents producing one triploid and one tetraploid. Genome-size estimates coupled with chromosome counts provide evidence for both one-step and two-step pathways in A. tridentata. A wild triploid produced viable offspring with varied aneuploidy (2n = 18 + 1 to 4n = 36 - 4) and genome sizes ranging from 11 pg to 18.2 pg.Conclusions: Our results indicate that one- and two-step pathways to WGD can occur in A. tridentata. The two-step pathway could provide a mechanism for bidirectional gene flow via triploid bridge. These pathways could generate substantial genomic variation within the A. tridentata polyploid complex. Given the fecundity and WGD rates in this species, the generation of polyploid offspring from diploid progenitors can be relevant to environmental adaptation at generational timescales.","PeriodicalId":7691,"journal":{"name":"American Journal of Botany","volume":"113 5","pages":"e70206"},"PeriodicalIF":2.8,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148004364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Climate and seed mass drive intraspecific variation in seed longevity in storage. 气候和种子质量驱动种子贮藏寿命的种内变异。

IF 2.8 2区生物学

American Journal of Botany Pub Date : 2026-05-01 Epub Date: 2026-05-07 DOI: 10.1002/ajb2.70202

Lea Klepka, Sascha Liepelt, Anna Bucharova

{"title":"Climate and seed mass drive intraspecific variation in seed longevity in storage.","authors":"Lea Klepka, Sascha Liepelt, Anna Bucharova","doi":"10.1002/ajb2.70202","DOIUrl":"10.1002/ajb2.70202","url":null,"abstract":"Premise: Conservation seed banks are essential for ex situ plant conservation, but stored seeds slowly deteriorate and lose viability. Seed longevity in storage is determined by the initial seed viability and the rate of seed viability loss. The rate of seed viability loss in storage varies between species and possibly between populations or even genotypes within species. However, the extent of this intraspecific variability and its drivers remain unclear.Methods: We investigated both inter- and intraspecific variability in seed longevity and its predictors in 41 common grassland species and 188 seed lots from across Europe. We exposed the seeds to simulated aging conditions (60% RH, 45°C) and used probit analysis to obtain the rate of seed viability loss (σ) as a measure of seed longevity. We then related σ to seed-lot- and species-specific factors.Results: Seed longevity (σ) varied significantly among seed lots within 58% of the species, and the probability of detecting such intraspecific differences increased with the number of seed lots available for a given species. This suggests that within-species variation in seed longevity is widespread. Seed-lot-specific predictors explained only 14.4% of the within-species variability. Specifically, seed longevity increased with the mean annual temperature at the seed lot origin and decreased with the seed-lot-specific seed mass. Across species, seed longevity differed among plant families but was unrelated to seed mass, protein, or oil content.Conclusions: Our findings highlight substantial within-species variation in seed longevity in storage, but it is difficult to predict.","PeriodicalId":7691,"journal":{"name":"American Journal of Botany","volume":" ","pages":"e70202"},"PeriodicalIF":2.8,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13206544/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147832548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Erratum to "Disentangling complex relationships and disjunctions in western Camassia: Integrating multiple criteria to resolve taxonomic boundaries". 对“解开西部Camassia的复杂关系和断裂：整合多个标准来解决分类界限”的勘误。

IF 2.8 2区生物学

American Journal of Botany Pub Date : 2026-05-01 Epub Date: 2026-05-19 DOI: 10.1002/ajb2.70209

引用次数: 0

Differential growth and physiological responses to water level and soil type in two dominant macrophytes, Cladium jamaicense and Muhlenbergia capillaris, in South Florida, USA. 美国南佛罗里达两种优势植物牙买加Cladium jamicense和毛缕木（Muhlenbergia capillaris）的生长差异及其对水位和土壤类型的生理响应。

IF 2.8 2区生物学

American Journal of Botany Pub Date : 2026-05-01 Epub Date: 2026-05-05 DOI: 10.1002/ajb2.70197

Paulo C Olivas, Jennifer H Richards, Steven F Oberbauer

{"title":"Differential growth and physiological responses to water level and soil type in two dominant macrophytes, Cladium jamaicense and Muhlenbergia capillaris, in South Florida, USA.","authors":"Paulo C Olivas, Jennifer H Richards, Steven F Oberbauer","doi":"10.1002/ajb2.70197","DOIUrl":"10.1002/ajb2.70197","url":null,"abstract":"Premise: Wetland ecosystems experience strong spatial and temporal fluctuations in water levels, superimposed on a mosaic of soil/nutrient regimes, so wetland macrophytes either avoid or tolerate inundation in the context of their soil environment. How do wetland plants adjust their physiology and morphology in response to these water levels and soil types, and what traits are linked to inundation tolerance or avoidance?Methods: In independent mesocosm experiments, we grew two co-occurring plant species: Cladium jamaicense, more commonly found in long-hydroperiod, peat environments, and Muhlenbergia capillaris, typically associated with short-hydroperiod, marl environments. Plants were subjected for a year to one of three water levels in marl or peat soils. Plant traits such as morphology, biomass, nutrient content, and photosynthetic capacity were evaluated.Results: Cladium jamaicense grew longer, wider leaves in response to higher water levels, whereas M. capillaris did not. Muhlenbergia capillaris photosynthetic rates were strongly reduced by high water level, while rates for C. jamaicense were less affected. Total biomass decreased with increasing inundation for both species, but shifts were only significant in M. capillaris.Conclusions: Cladium jamaicense adjusted leaf morphology to both water level and soil type, whereas M. capillaris did not. Cladium jamaicense showed a growth response to avoid flooding, which was enhanced in peat soils, while M. capillaris showed a tolerance response, which was unaffected by soil type. These results can be used to predict these species' responses to hydrologic and nutrient changes and distributions in other wetlands and to infer traits of other wetland species and their consequent distributions along hydrologic and soil gradients.","PeriodicalId":7691,"journal":{"name":"American Journal of Botany","volume":" ","pages":"e70197"},"PeriodicalIF":2.8,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147832606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Sex-biased seed predation in a gynodioecious species, Sidalcea campestris. 雌蕊异株种的性别偏向种子捕食。

IF 2.8 2区生物学

American Journal of Botany Pub Date : 2026-05-01 Epub Date: 2026-05-13 DOI: 10.1002/ajb2.70207

Brooklyn A Richards, Susan M Waters, F Andrew Jones, Thomas N Kaye

{"title":"Sex-biased seed predation in a gynodioecious species, Sidalcea campestris.","authors":"Brooklyn A Richards, Susan M Waters, F Andrew Jones, Thomas N Kaye","doi":"10.1002/ajb2.70207","DOIUrl":"10.1002/ajb2.70207","url":null,"abstract":"Premise: The coexistence of females and hermaphrodites, or gynodioecy, requires that females have a reproductive advantage over hermaphrodites in offspring quality and/or quantity. Female advantage can be mediated by a variety of ecological factors, including interactions with antagonists such as pre-dispersal seed predators. We compared differential rates of seed predation on hermaphrodites and females in Sidalcea campestris to assess the potential role of seed predators in gynodioecy maintenance.Methods: We evaluated rates of seed predation in 28 populations of S. campestris, a gynodioecious, insect-pollinated herbaceous perennial. By dissecting fruits of hermaphrodite and female plants in each site, we tested how plant sex and population female frequency influence the proportion of fertilized ovules consumed by pre-dispersal seed predators.Results: The specialist pre-dispersal weevil seed predator Macrorhoptus sidalceae was detected in 24 (86%) study populations. Across all sites, average predation levels ranged from zero to 85%. Seed predation rates were approximately 1.35× higher in hermaphrodites than in females. Seed predation rates were unaffected by population-level female frequency.Conclusions: Hermaphrodite fruits experienced higher seed predation rates than female fruits, regardless of population female frequency. Pre-dispersal seed predators may influence sex-specific reproductive success and potentially contribute to female advantage in S. campestris, though additional ecological and genetic factors may regulate population female frequency in this system. Our study highlights the importance of considering how non-pollinator agents of selection, such as seed predators, potentially influence floral trait evolution and the evolution of sexual systems more broadly.","PeriodicalId":7691,"journal":{"name":"American Journal of Botany","volume":" ","pages":"e70207"},"PeriodicalIF":2.8,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147925579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The danger zone: The joint trap of incomplete lineage sorting and long-branch attraction in resolving the Gondwanan origin of Rafflesiaceae and Apodanthaceae. 危险地带：不完全谱系分选和长枝吸引联合陷阱在解决蛇麻科和蛇麻科冈瓦纳起源中的作用。

IF 2.8 2区生物学

American Journal of Botany Pub Date : 2026-05-01 Epub Date: 2026-05-12 DOI: 10.1002/ajb2.70201

Liming Cai, Natalia Pabón-Mora, Juan F Alzate, Liang Liu, Charles C Davis

{"title":"The danger zone: The joint trap of incomplete lineage sorting and long-branch attraction in resolving the Gondwanan origin of Rafflesiaceae and Apodanthaceae.","authors":"Liming Cai, Natalia Pabón-Mora, Juan F Alzate, Liang Liu, Charles C Davis","doi":"10.1002/ajb2.70201","DOIUrl":"10.1002/ajb2.70201","url":null,"abstract":"Premise: Rafflesiaceae (Malpighiales) is an iconic parasitic plant clade of species that occur west of Wallace's line in tropical Southeast Asia. This clade has been notoriously difficult to place phylogenetically and is nested within an explosive ancient radiation in Malpighiales, rendering one of the thorniest nodes across the angiosperm Tree of Life. The parasitic family Apodanthaceae has recently been positioned as sister to Rafflesiaceae, offering hope of stabilizing their placements.Methods: Here, using a data set of 2135 genes and complex methods for species tree inference, we aimed to resolve the phylogenetic placement and divergence time of Rafflesiaceae and Apodanthaceae. We also applied computational simulation to investigate the impact of incomplete lineage sorting (ILS) and long-branch attraction on resolving this ancient radiation.Results: The clade comprising Rafflesiaceae and Apodanthaceae was variously placed with Euphorbiaceae, Peraceae, Putranjivaceae, and Pandaceae by coalescent and concatenation methods. Such unstable placements appear to be the result of excessive levels of rate heterogeneity and ILS, which contribute to a phylogenetic \"danger zone\" where simulation suggests that current methods and genomic data may never provide a tidy species tree.Conclusions: Despite the topological uncertainty, our divergence time estimation identified a mid-Cretaceous origin of stem group Rafflesiaceae and Apodanthaceae, not only making them the oldest parasitic plant lineage reported to date, but also suggesting a likely Gondwana vicariance scenario that explains their initial disjunct distribution in Northern India, Australia, South America, and Africa.","PeriodicalId":7691,"journal":{"name":"American Journal of Botany","volume":" ","pages":"e70201"},"PeriodicalIF":2.8,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147873131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Beyond poikilothermy: Habitat and sex shape thermoregulation and its impact on resilience to heat in the liverwort Marchantia inflexa. 超越变温：地茅的生境和性别形态体温调节及其对热恢复力的影响。

IF 2.8 2区生物学

American Journal of Botany Pub Date : 2026-05-01 DOI: 10.1002/ajb2.70205

Hansika K Herath, Callie A Ellis, D Nicholas McLetchie

{"title":"Beyond poikilothermy: Habitat and sex shape thermoregulation and its impact on resilience to heat in the liverwort Marchantia inflexa.","authors":"Hansika K Herath, Callie A Ellis, D Nicholas McLetchie","doi":"10.1002/ajb2.70205","DOIUrl":"10.1002/ajb2.70205","url":null,"abstract":"Premise: Elevated air temperatures subject plants to heat stress, impairing their physiology and productivity. Because most studies on heat resilience have focused on ambient air rather than tissue temperatures, our understanding of how plants perceive and respond to heat remains limited. We evaluated how tissue temperature and thermoregulation varied during heat stress, quantified the damage and recovery of photosystem II (PSII), and related thermoregulation to recovery.Methods: We grew male and female plants of the thalloid liverwort Marchantia inflexa that originated from two contrasting habitats (streamsides and roadsides) in common conditions to capture natural variation in temperature parameters; 42 plants were placed in an oven for 45 min at 55°C, and tissue temperatures were recorded every 10 s. Thermoregulation was assessed as mean fluctuations of tissue temperatures, and damage and recovery were assessed using PSII efficiency.Results: Thallus temperatures mirrored thermoregulatory patterns; they were higher on roadsides and in females and more variable in males. Although recovery patterns across habitats aligned positively with thermoregulation, streamside males exhibited the opposite pattern.Conclusions: We posit these patterns reflect stronger selection for thermoregulation in plants on roadsides than on streamsides, and stronger selection in females to optimize photosynthesis to support maturing offspring.","PeriodicalId":7691,"journal":{"name":"American Journal of Botany","volume":"113 5","pages":"e70205"},"PeriodicalIF":2.8,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148004345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0